"""Provider-neutral fallback contracts for Hermes automatic routing."""

from __future__ import annotations

import tomllib

from testing.tests.test_hermes_chat_support import HERMES, _documents


def _config() -> dict:
    manifest = _documents(HERMES / "switchyard-configmap.yaml")[0]
    return tomllib.loads(manifest["data"]["routes.toml"])


def _provider(target_id: str) -> str | None:
    parts = target_id.split("/")
    if len(parts) >= 3 and parts[0] in {"route", "worker"}:
        return parts[1]
    return None


def test_every_classifier_selects_from_both_hosted_providers():
    """No automatic classifier may narrow its candidate set to one provider."""
    config = _config()
    targets = config["targets"]
    classifiers = {
        name: route
        for name, route in config["routes"].items()
        if route["type"] == "llm_classifier"
    }

    assert classifiers
    for route in classifiers.values():
        providers = {
            _provider(targets[name]["id"])
            for name in route["targets"]
        }
        assert {"codex", "claude"} <= providers


def test_classifier_failure_uses_an_even_cross_provider_pool():
    """The required Switchyard default must name a neutral pool, not a provider."""
    config = _config()
    targets = config["targets"]
    routes = config["routes"]
    routes_by_id = {route["id"]: route for route in routes.values()}

    for route in routes.values():
        if route["type"] != "llm_classifier":
            continue
        fallback_target_name = route["default_target"]
        assert fallback_target_name in route["targets"]
        assert fallback_target_name.startswith("neutral_")
        fallback_target = targets[fallback_target_name]
        assert fallback_target["llm_client"] == "neutral_pool"

        pool = routes_by_id[fallback_target["id"]]
        assert pool["type"] == "random"
        assert pool["weights"] == [1.0, 1.0]
        pool_providers = [
            _provider(targets[name]["id"])
            for name in pool["targets"]
        ]
        assert sorted(pool_providers) == ["claude", "codex"]

    neutral_client = config["llm_clients"]["neutral_pool"]
    assert neutral_client == {
        "format": "openai_chat",
        "base_url": "http://127.0.0.1:9005/v1",
        "max_retries": 0,
    }